California took the fast lane to the future on Tuesday when Gov. Jerry Brown signed a law that lets self-driving cars onto public roads.

Brown rode to the signing ceremony at Google headquarters in the passenger seat of a vehicle that steered itself, a Prius modified by Google. Google co-founder Sergey Brin and State Sen. Alex Padilla, who sponsored the bill, were along for the ride. An engineer for the technology company, Chris Urmson, sat in the driver's seat, but the car drove itself.

"We're looking at science fiction becoming tomorrow's reality," Brown said just before signing the bill.